[21p-W241-1~21] 10.2 Spin torque, spin current, circuits, and measurement technologies

▼ [21p-W241-18] Influence of spin polarization of SIL on oscillation behavior of a mag-flip
spin-torque-oscillator (STO) device

〇Hossein SepehriAmin¹, S. Bosu¹, Y. Sakuraba¹, M. Hayashi¹, T. Schrefl², C. Abert³, D. Suess³, K. Hono¹ (1.NIMS, Tsukuba, Japan, 2.Danube University Krems, Austria, 3.Technical University of Vienna, Austria)

Keywords:Spin-Torque-Oscillator,Spin Polarization,Micromagnetic Simulations

Microwave assisted magnetic recording (MAMR) is considered as one of good candidates for next generation higher areal density magnetic recording technology. For MAMR writer, mag-flip spin-torque-oscillator (STO) that can produce microwave frequency of above 20 GHz induced by a current with its density below 1.0×10⁸ A/cm² is required. However, this has not been realized experimentally. In this work, we employed micromagnetic simulations to study the effect of spin polarization (β) of a spin injection layer (SIL) on the oscillation behavior of a mag-flip STO devices. Micromagnetic simulations showed that J_C can be substantially reduced by using a material with high spin polarization as SIL. In addition, increase of spin polarization of SIL led to increase of microwave frequency peak as well as oscilation cone angle of field generating layer (FGL). The underlying physics of this will be explained based on our calculations on the spin accumulations.